NHC - Steering problem

[rangaraj]

Hi,

Overheard this from a friend, but thought it might be useful for some of you to dig up more information.

This colleague's friend was driving on the highway in a NHC and at around 90kmph he lost total control of the steering and jammed the brakes, did a spin, but luckily was not hurt.

He took it to the dealer and they did a computer dump and figured out that there is a active speed sensitive power steering (the baleno also has this) and this is connected to the odometer (?). Apparently they noticed in the graph that there was a glitch in communication between the odo and the active steering control and that may have caused it. This guy then came back with his lawyer and wanted access to the information and then the honda guys denied access to it. He has filed a case against them.

Wanted to check if there are any problems of a similar nature that any of you have faced? Does anyone have some concrete proof of something similar hapenning in other cars?

I remember taking a mercedes cab in amsterdam and a morrocan driver was as usual driving at 150+kmph and suddenly from the fast lane he swung to the slowest lane and then to the service lane - switched off his engine and restarted the engine and continued with the journey. On probing him, he mentioned that there was a software glitch that the merc guys could not solve - everytime he hears a metallic click, he knows that in 15-20 secs the engine shuts off and hence this crazy and desperate urgency to stop and resart the engine (of course many drivers were cursing him). So i know this is not an isolated incident and is due to software glitches...

thoughts???

ranga raj

[WhiteKnight]

Originally Posted by rangaraj

Hi,
He took it to the dealer and they did a computer dump and figured out that there is a active speed sensitive power steering (the baleno also has this) and this is connected to the odometer (?). Apparently they noticed in the graph that there was a glitch in communication between the odo and the active steering control and that may have caused it.
ranga raj

Too much technology is a pain sometimes. This appears to be a problem with Electronic power steering. But I do not understand the steeting being linked to the Odo part.
Anybody help?

[sharathjeppu]

Originally Posted by rangaraj

He took it to the dealer and they did a computer dump and figured out that there is a active speed sensitive power steering (the baleno also has this) and this is connected to the odometer (?).

Odometer or speedometer? Speedometer sounds more logical.

[ajmat]

Originally Posted by rangaraj

. On probing him, he mentioned that there was a software glitch that the merc guys could not solve - everytime he hears a metallic click, he knows that in 15-20 secs the engine shuts off and hence this crazy and desperate urgency to stop and resart the engine (of course many drivers were cursing him). So i know this is not an isolated incident and is due to software glitches...

Case of rushing into production too soon

That's why Mercedes are withdrawing the sensotronic brakes from the E- class which were never fitted on the new S class. They have resolved no more new electronic gizmo's until thoroughly proven.

Honda's case is unusual. It has electronic power steering which means possible trouble. What ever happened to good old hydraulic and vaccum systems !

[sumitkalindi]

This is scary, my next car is not going to have any electronic controlled things. I dont want to do this stunts in the hills.

[rangaraj]

Originally Posted by sharathjeppu

Odometer or speedometer? Speedometer sounds more logical.

Speedo it is.. Sorry about that..

[WhiteKnight]

Originally Posted by rangaraj

Speedo it is.. Sorry about that..

Speedo comes into pic only in terms of deciding the sensitivity of the power steeting. That doesn't explain this case where the driver completely lost control.
I think this is a much more serious problem

[Buffetfan]

Originally Posted by ajmat

Case of rushing into production too soon

That's why Mercedes are withdrawing the sensotronic brakes from the E- class which were never fitted on the new S class. They have resolved no more new electronic gizmo's until thoroughly proven.

Honda's case is unusual. It has electronic power steering which means possible trouble. What ever happened to good old hydraulic and vaccum systems !

To the best of my knowledge...honda City has hydraulic power steering...and Baleno has the same too...big vehicles generally do not have electric power steerings due to the demand it puts on the alternator

[RX135]

Originally Posted by Buffetfan

To the best of my knowledge...honda City has hydraulic power steering...and Baleno has the same too...big vehicles generally do not have electric power steerings due to the demand it puts on the alternator

Nope, sir! NHC always had electric power steering. Baleno has hydraulic power steering.

[rangaraj]

Originally Posted by RX135

Nope, sir! NHC always had electric power steering. Baleno has hydraulic power steering.

Can we compile a list of cars sold in India that have speed sensitive power steerings and which ones are electric and which ones are hydraulic..

NHC - Electric
Baleno - Hydraulic (Thank god!)

[ECM]

One thing is always common in most of car in India(correct me if I am wrong) which ever they are that when speed go above 70kmph steering sence the pulse fm speedo meter and isolate itself and stop working as a Power steering and becomes slightly hard to avoid crash,this is for safety but I don't know how this has happened !

[sharathjeppu]

Originally Posted by rangaraj

NHC - Electric
Baleno - Hydraulic (Thank god!)

I think all the Maruti Vehicles with Power Steering (except the Baleno) come with Electric Power Steering. (Alto, Wagon R, Zen & Esteem)

[narasimha raju]

Any Power Streering either electronic or hydraulic are speed sensitive. The power assist will he high at zero speed and gradually decreases when the vehicle reaches higher speeds. There will be no power assist to the steering after 60 KMPH.

So whether it is Electronic/Hydraulic, The controller of the power assist is software which decides how much power assist is required for a specific speed.

I think the cause of the problem in NHC might be because of high power assist continued even after 60 KMPH (might be due to software glitch or some sensor failure) and a slight turn of streering at that speed will cause lot of turn in the wheel and caused vehicle spin.

[vipul_singh]

Hi,

I am not quite able to understand how the NHC driver lost control of the car completely. The speed sensitive EPS system varies the *level of assistance* available to the driver. It takes as an input the speed of the vehicle. If there is a glitch in communications from the speedo, the steering would become heavier/lighter than usual, but the driver is unlikely to lose control since (by law) there is always a physical link between the wheels and the steering wheel, and a variation in the input from the speedo cannot cause the EPS to turn the vehicle on its own. Nor can it cause a slight turn of the steering wheel to get amplified at the front wheels, since the EPS *does not change the steering ratio* (please correct me if I am wrong).

I wonder if something else caused the loss of control, instead of the EPS system.

[narasimha raju]

Originally Posted by vipul_singh

Nor can it cause a slight turn of the steering wheel to get amplified at the front wheels, since the EPS *does not change the steering ratio* (please correct me if I am wrong).

You are correct. The power assist will not change the streeing ratio. As per my experience, NHC streering feels much lighter at higher speeds. You will feel like the car is flying in the air and not planted to the road.

If there is any problem with the EPS, the EPS light in speedo will glow and the power assist will be cancelled to the steering. So that should not cause any problem.